Walter a



(Nd Model.)

A.'HEATQH, A. L. JACOBS & A. M. KING.

SLIDING DOOR OPERATING MECHANISM.

Patented Jan. 19, 18.97.

TVALTER A. HEATI'I, ABRAHAM L. JACOBS, AND ALBERT M. KING, OFWILMINGTON, DELAW'ARE; SAID HEATH ASSIGNOR TO SAID JACOBS AND KING.

SPECIFICATION forming part of Letters Patent No. 575,644, dated January19, 1897.

Application filed February 27, 1896. Serial No. 580,977. (No model.)

To a. whom, it iii/(by concern:

Be it known that we, WALTER A. HEATH, ABRAHAM L. J ACOBS, and ALBERT M.KING, citizens of the United States, residing at Vilmington, in thecounty of New Castle and State of, Delaware, have invented new anduseful Improvements in Sliding-Door-Operating Mechanisms, of which thefollowing is a specification.

This invention relates to sliding doors, and has. for its objects toprovide new and improved means whereby the sliding movement of one dooris transmitted to another door in such manner that both doors open orclose simultaneously and to provide novel means whereby either of thedoors is susceptible of yielding or giving slightly at the bottom forthe purpose of effectually preventing any binding of the devices bywhich the motion of one door is transmitted to the other door.

To accomplish these objects, ourinvent-ion consists in the features ofconstruction and in the combination or arrangement of partshereinafterdescribed and claimed, reference being made to theaccompanying drawings, in which Figure 1 is a front elevation of twosliding doors provided with our invention and shown in their closedposition. Fig. 2 is a detail vertical sectional view taken on the line 22, Fig. 1; and Fig. 3 is a detail sectional view of the 11011 rotarynuts, showing portions of the screw-threaded shaft on a larger scalethan Fig. l for the purpose of more clearly illustrating the parts.

In order to enable those skilled in the art to make and use ourinvention, we will now describe the same in detail, referring to thedrawings, wherein- The numerals 1 and 2 indicate the two sliding doorsor door-sections, which may be of any desired construction or form andbe provided respectively, with any suitable handles 3 and 4:. The doorsare provided at their upper ends with non-rotary right and left handinternally-screw-threaded nuts 5 and 6, which respectively engage theright and left screwthreads 7 and 8, formed on or in the exterior of ahorizontal shaft arranged directly above the top edges of the two doors.I This shaft is supported at its ends in metallic bearingblocks 9 and1.0, secured by screws or otherwise to the door-frame, and centrallybetween its ends the shaft extends through and is sustained by a hanger12 on the door-frame, the construction of all these parts being suchthat the externally right and left hand screwthreaded shaft is free tobe rotated.

The shaft may be a cylindrical bar or rodhaving the right and left handscrew-threads cut directly into the surface thereof, or the shaft may besquare or triangular in crosssection and twisted in reverse directionsfrom about its central portion in such manner as to form the externalright and left hand screwthreads.

The non-rotary nuts are each provided with a jointed or pivotalconnection with one of the sliding doors, and, as shown, this isaccomplished by .providing the nuts with pendent tailpieces 13 and 14,which are pivoted by pins, bolts, or rivet-s 15 and 16 to the upper endsof metallic door-hanger plates 17 and 18. The pivot-pins, bolts, orrivets 15 and 16 are arranged at right angles to the plane of motion ofthe doors in such manner that either door is susceptible of yielding ina plane parallel with the line of motion of the doors. The hanger-platesare firmly attached by screws or other devices to the upper end portionsof the sliding doors, and the doors themselves are preferably recessed,as at 19, Fig. 2, for the purpose of accommodating the tailpieces 13 and14 and the pivots which connect the tailpieces to the door-hangerplates.

As shown in the drawings, the non-rotary screw-threaded nuts 5 and 6 arearranged in proximity to the inner or meeting edges of the two doors,and supplemental devices are provided which will maintain theperpendicularity of the doors and enable them to he slid freely back andforth to their opened or closed positions.

The supplemental supporting devices are preferably arranged near theupper ends of the doors at the outers edges thereof, and are composed ofroller-bearings or Wheels 20 and and 21, and rails or tracks 22 and 23on which the roller-bearings or wheels travel when the doors are moved.The roller-bearings or wheels may also bear against guide rails orstrips 2i and 25, arranged above and parallel with the rails or tracks22 and 23 for the purpose of more securely retaining the roller-bearingsor wheels in operative connection with the rails or tracks.

The rails or tracks and the guide rails or strips are secured tothedoor-frame and the roller-bearings or wheels are mounted in brackets 26and 27, attached to the edges of the doors and oifset sufficiently tosupport the roller-bearings or wheels, so that they can traverse theails or tracks while permitting the doors to move beside or in front ofthese rails or tracks, as will be obvious without further explanation.

The external right and left hand screwthreads of the shaft and theinternal screwthreads of the non-rotary nuts should be accura-tely andnicely formed and fitted together, so that the parts will easily operatewhen either door is moved.

The jointed or pivotal connections between the doors and the non-rotarynuts render it possible for the door to yield or give slightly at thebottom in a plane parallel with the line of motion of the doors toeffectually prevent binding of the nuts on the screwthreaded shaft,which binding would be likely to result if the roller-bearin gs were notso constructed and arranged as to permit a slight tilting motionperpendicularly of the doors when power is applied to either door toslide the same.

The screw-threads of the shaft may be single or double, but preferablywe employ double screw-threads, as such construction secures amore rapidmovement of the nuts, and consequently the doors can be more swiftlyopened or closed.

The invention is particularly useful at the front and rear ends ofrailway passenger-oars, but we wish it clearly understood that we do notlimit ourselves to any particular use of our improved door-operatingmechanism, as obviously it can be applied to sliding doors designed forbarns, dwellings, freight and other railway cars, and, in fact, whereversliding doors are employed.

In manufacturing the screw-nuts we prefer to cast hollow blanks of brassor bronze metal, then place these blanks on a metal pattern having scrcnthreads of the same pitch as the rotary shaft and pour or cast inBabbitt metal to form the screw-threads in the nuts. This produces anaccurate fit of the nuts and shaft, so that these parts will easily,nicely, and smoothly work.

Having thus described our invention, what we claim is- 1. Thecombination with a pair of sliding doors, of a right and left handscrew-threaded shaft, right and left hand internally-screwthreaded nutsengaging said shaft, and jointed connections between the nuts and theupper ends of the doors, whereby the lower end of either door issusceptible of yielding in a plane parallel with the motion of the doorsto prevent binding between the nuts and the shaft, substantially asdescribed.

2. The combination with two sliding doors, of a right and left handscrew-threaded shaft, right and left hand internally-screw-threaded nutsengaging said shaft and serving to 1'0- tate the same when movedlongitudinally thereof, door-hanger plates secured to the upper ends ofthe doors, and pivot-pins arranged at right angles to the line of motionof the doors and pivotally connecting the doorhanger plates with thescrew-threaded nuts, substantially as and for the purposes described.

3. The combination with two sliding doors, of a right and left handscrew-threaded shaft, screw-threaded nuts engaging said shaft andconstructed with pendent tailpieces,and doorhanger plates secured to theupper ends of the doors and pivotally connected with the said pendenttailpieces of the screw-threaded nuts, whereby the motion of either nutserves to rotate the shaft and either door is susceptible of yielding ina plane parallel with the plane of motion of the doors, substantially asand for the purposes described.

In testimony whereof we have hereunto set our hands in presence of twosubscribing witnesses.

WALTER A. HEATH. ABRAHAM L. JACOBS. ALBERT M. KING.

\Vitnesses:

WALKIN L. STRAHORN, CHARLES H. Scorn

